In the case of a computer program running under an operating system however graphics are also defined by the computer program itself and simply transferred to the operating system, which then does not influence the graphics further but causes the graphics to be represented on a display apparatus by way of control commands to the display apparatus. Some computer programs allow settings governing how such graphics are represented to be selected. However this selection option is not standard.
Different graphic configurations may be necessary depending on the environment of the display apparatus. In a clinical environment there is for example a very bright working environment in a reception area where patients are booked in. The reception area is comparable to an office area. Screens in the office area typically have a luminance of 120 cd/m2. However so-called diagnostic work stations are also present in the clinical environment. The German x-ray ordinance requires a dark environment for these. In contrast screens at diagnostic work stations should have a luminance of 400 cd/m2.
Comparing these two extremes highlights a general need to tailor the representation of graphics to the environment of a display apparatus on which they are represented. Depending on the environment a certain brightness may be required for the graphic, a certain contrast may be advantageous and certain color values may also be particularly easily visible to the human eye.
It would be desirable for it to be possible to tailor the characteristics of graphic elements produced by a computer program operating under an operating system and displayed on a display apparatus to ambient conditions in a variable manner.